1. Field of the Invention
The present invention relates to the preparation of amendments and fertilizer products for agricultural soils by entrapment of acid gases contained in atmospheric air containing oxides and/or hydrated oxides of carbon and/or sulfur. The acidic gases are entrapped by solid waste material generally referred to as "garbage".
2. Description of the Related Art
Calcium oxide in its various forms is found in many alkaline earth compounds such as calcite, aragonite, dolomite, and limestone as calcium carbonate (CaCO.sub.3), burnt lime (CaO), slaked and hydrated lime (Ca(OH).sub.2), and calcium-magnesium carbonate (CaMgCO.sub.3). It has been suggested to use calcium oxide in its various forms in the presence of water, usually as a slurry or a watery paste of varying viscosities, to react and combine chemically with sulfur dioxide (SO.sub.2) and sulfur trioxide (SO.sub.3) gases. These gases are present in acidic gases derived from burning coal and other combustible organic type matter containing sulfur, and from conversion by roasting (oxidation) of sulfide forms of sulfur present in sulfide sulfur types of ores. These sulfur oxide gases are brought into contact with such lime-containing slurries to "trap" the gases, i.e., to cause chemical combination of the sulfur oxide gases with the lime slurries to form slurries containing products of alkaline neutralization wherein the lime (CaO) has reacted with the sulfur oxides to form hydrates of calcium sulfite (CaSO.sub.3.xH.sub.2 O) and some calcium sulfate hydrate (CaSO.sub.4.xH.sub.2 O). Other approaches for entrapment of acidic gases have involved spraying of "solutions" of various alkaline liquids containing suspensions of lime directly into the acid gases, which are essentially atmospheric gas borne carbon and sulfur oxides, to form neutralized and semi-neutralized calcium carbonates, bicarbonates, sulfites, bisulfites, sulfates, and bisulfate salts of calcium of varying degrees of hydration. Other processes such as disclosed in Wilson U.S. Pat. No. 3,882,221 have used fluid bed reactors where the acid gases are caused to come into contact with alkaline (NaOH) coated particles of acid-undecomposable siliceous matter in the presence of controlled amounts of water. All of these processes essentially rely on applications of chemistry where sulfur oxide gases combine with water to form sulfurous and sulfuric acids which react chemically with alkali and alkaline earth hydrated oxides to form sodium or calcium salts of oxides and hydrated oxides of carbon and sulfur.